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  1. #16
    whatup777+'s Avatar
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    Quote Originally Posted by mmbob View Post
    memcpy is (at least with Visual Studio) an optimized assembly function. Hand written assembly will nearly always be faster than C++, unless the assembly coder has no idea what he is doing. I believe memcpy copies in DWORD chunks also, which would make it much faster than a for loop.
    Nigga knows shit.

  2. #17
    Departure's Avatar
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    Then may I suggest inline assembly using the "mov" assembly statement

  3. #18
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    Quote Originally Posted by Departure View Post
    Then may I suggest inline assembly using the "mov" assembly statement
    you can only copy/write 1, 2 or 4 bytes with mov.

    Code:
    mov byte ptr [address], al
    mov word ptr [address], ax
    mov dword ptr [address], eax
    Last edited by Gordon`; 02-09-2011 at 10:34 PM.


  4. #19
    Departure's Avatar
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    Yes true Gordon, if you do a straight mov... Look at example below to explain what I mean using REP MOVSB

    Code:
    procedure CopyMemory(Destination, Source:Pointer; dwSize:LongWord);
    asm
      PUSH ECX
      PUSH ESI
      PUSH EDI
      MOV EDI, Destination
      MOV ESI, Source
      MOV ECX, dwSize
      REP MOVSB
      POP EDI
      POP ESI
      POP ECX
    end;

    All we do here is use MOVSB which will mov bytes from address in ESI to address in EDI, this will repeat using the REP statement Untill ECX = 0 allowing us to use any amount of bytes.

    Reference
    http://faydoc.tripod.com/cpu/movsb.htm
    Last edited by Departure; 02-10-2011 at 02:55 AM.

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